#include <iostream> using namespace std; int main() { int score; cin >> score; // write your code here...... if (score < 0 || score > 100) { cout << "成绩不合法" << endl; } else if (score < 60) { cout << "差" << endl; } else if (score < 70) { cout << "及格" << endl; } else if (score < 80) { cout << "中" << endl; } else if (score < 90) { cout << "良" << endl; } else { cout << "优秀" << endl; } return 0; }